1. Field of the Invention
The present invention relates to a stationery tool and, more particularly, to a thin film dispenser having a push button to control a dispensing head to extend out of or be retracted into a body of the dispenser.
2. Description of Related Art
A conventional correction tape dispenser can control a dispensing head of a dispensing unit extending out of or being retracted into a body in a manner of pushing to dispense a correction tape onto a sheet of paper or the like to correct errors on the paper. Taiwan Patent Publication No. 200720109, entitled “Coating Film Transferring Tool”, discloses a pushing structure for controlling the dispensing unit. With reference to FIGS. 29 and 30, the '109 patent discloses a body 50, a dispensing unit 51 and a push button 54. The body 50 has an elongated slot 53 defined in one side of the body 50. The slot 53 has two pairs of positioning recesses 530,531 defined respectively in two side walls of the slot 53 and are respectively adjacent to a rear end and a middle of the slot 53. The dispensing unit 51 is mounted in the body 50. The push button 54 is connected to the dispensing unit 51 and is slidably mounted in the slot 53. The push button 54 has a V or Y shaped resilient positioning element 540 mounted on the push button 54 and mounted slidably in the slot 53. Two ends of the resilient positioning element 540 selectively engage one of the pairs of positioning recesses 530,531 to hold a dispensing head of the dispensing unit 51 at an expended or retracted position relative to the body 50.
When the push button 54 slides along the slot 53, the ends of the V or Y shaped resilient positioning element 540 will be compressed by the side walls of and slide along the slot 53. However, the forces applied to the ends of the resilient positioning element 540 while the push button 54 is pushed to move forward and backward are different and in different directions, and the movement of the push button 54 is uneven and not smooth. In addition, the push button 54 is held in position with the engagement between the ends of the resilient positioning element 540 and the corresponding positioning recesses 530,531, and the positioning effect provided by the resilient positioning element 540 is not sufficient to securely hold the push button 54. When the dispensing head of the dispensing unit 51 is pushed onto a paper for dispensing the correction tape, a force is applied onto the dispensing head and causes the ends of the resilient positioning element 540 to disengage from the corresponding positioning recesses 531. Consequently, the dispensing unit will retract into the body 50 unintentionally, and this causes inconvenient use.
In addition, to improve the utility of a conventional correction tape dispenser, a rubber is mounted on the conventional correction tape. Taiwan Utility Model No. M323995, entitled “Dual Purpose Correction Tape”, discloses a rubber pressed into a body of a correction tape dispenser. With reference to FIG. 31, the correction tape dispenser of the '995 patent comprises a body 60 having a holding recess 61 defined in a rear end of the body 60. A rubber 62 is pressed into and securely held in the holding recess 61, and a cap 63 is detachably mounted on the rear end of the body 60 to hold the rubber 62 inside to prevent the rubber 62 from being dirtied. In use, the body 60 is upside down to enable the rubber 62 to correct errors on the paper made by a pencil. With such an arrangement of the rubber 62, the alternative use of the correction tape and the rubber 62 is convenient, and the rubber 62 can be kept from disappearing.
However, since the rubber 62 is mounted securely on the body 60, and as long as deformation of the rubber 62 occurs, the rubber 62 is easily detached from the body 60 when wiping pencil marks out. In addition, the extension length of the rubber 62 cannot be adjusted relative to the body 60, and the rubber 62 cannot be retracted into or extended out of the body 60. This is not versatile in use. Furthermore, when the rubber 62 is used up or damaged, the used rubber 62 cannot easily be removed from the body 60 and replaced with a new one.
To overcome the shortcomings, the present invention provides a thin film dispenser to mitigate or obviate the aforementioned problems.